Racial and ethnic differences in ocular anatomy.

Differences in eyelid structure are well described in the literature with respect to the Asian eyelid, but discussion of differences in eyelid structure between the other races is scarce. Most of the literature focuses on distinctions between “double” and “single” eyelids. Other clinical and surgical considerations are the presence of epicanthi and palpebral fissure slant. By understanding racial and ethnic anatomical differences, oculoplastic surgeons will be able to optimize function and aesthetics. Asians may have fuller, thicker-appearing upper eyelids with an absent or relatively lower upper lid (supratarsal) fold, making the distinction between the single and double eyelid (Figs 1, 2). The orbital septum of Asians fuses with the levator palpebrae aponeurosis at variable distances below the superior tarsal border, closer to the eyelid margin than in non-Asians. This hinders aponeurotic fibers from the levator palpebrae superioris from reaching the subcutaneous tissues, prohibiting the creating of a double eyelid crease. The fusion is above the superior tarsal